The task of obtaining high-quality time-resolved volumetric images of the heart has challenged the minds of imaging researchers for decades. While this problem is difficult, the high incidence of cardiovascular disease (CVD) in the developed world today makes finding a solution all the more urgent. Indeed, CVD is currently the most common cause of death in the United States. In this context, the role of imaging is dual; it can provide early diagnosis and can also enable cost-effective treatment of heart disease. This presentation will focus on how to perform these tasks using computed tomography (CT), while delivering a minimal dose of ionizing radiation. The enabling technology is the prior image constrained compressed sensing (PICCS) image reconstruction framework, which was developed and implemented at the University of Wisconsin-Madison. Two applications of PICCS will be examined: CT myocardial perfusion imaging and time-resolved interventional cardiac cone-beam CT. Several technical issues specific to these applications will be described. The performance of the method will be characterized using quantitative image quality metrics so as to determine its limitations. At the conclusion of the presentation, the audience should better understand the potential role of PICCS in cardiac CT at the diagnostic and the interventional levels.